Rail-pushing car

ABSTRACT

A railway car ( 100 ) for placing long rails onto a railway platform, includes a rear end ( 200 ) hitched to a rail transport car and a front end ( 400 ) and further including, on the rear end ( 200 ) thereof, at least one element ( 202   a,    202   b ) for longitudinally removing a rail from a rail storage arranged on the rail transport car and at least one first element for driving the rail such as to move the rail to the front of the car. The first drive element takes up the rail between two motor-driven tracked trains, each including a tracked belt sent between two wheels, the tracked trains being provided such as to take a relative position in which the tracked belts face each other and the axles of the wheels are vertical.

The present invention relates to a railway wagon car suitable for the laying of rails for a railway track under construction. It also relates to a method of laying the rails using in particular such a car.

The development of railway lines for high speed trains in particular has led to the search for new ways and new methods for constructing these railway tracks in the most economical way possible. Conventional methods using temporary elements, such as panels of rails measuring 18 metres in length consisting of sleepers made of timber wood, are not economical. The most recent methods limit the use of temporary elements that require heavy logistics, by the laying of elements, rails and sleepers that are permanent. These methods are also oriented towards the continuous rather than the jointed track method for the laying of these elements.

It should be recalled that current railway tracks are constructed based on “continuous welded rails” (CWR), which can measure more than 100 m long, laid on reinforced concrete sleepers (RCS). The CWRs require specific means of handling. They are delivered to construction sites stored on racks of rail transport wagon cars hitched to each other.

From the document EP 0 853 160 a wagon car for unloading long rails is known that comprises a rail unloading device, comprising of:

-   -   a gripping hook, a cable and a cable winch for removing a rail         from a stored stock of rail arranged on a railway wagon car,     -   a rail unloading device comprising of, on the one hand, a         tracked belt sent around by return pulleys with a horizontal         axis transverse to the railway wagon car, the elements of the         tracked belt being supported under the foot of the rail in order         to drive and unload the rail, and on the other hand, the pulleys         located above the rail that run over the head of the rail. The         rail is clamped between the tracked belt and the pulleys along a         vertical direction and driven by means of friction on the         elements of the tracked belt.

In a variant, the device comprises of two tracked belts, one upper tracked belt over, and one lower tracked belt below the rail, but the return pulleys are always with a horizontal axis and there is always one tracked belt under the rail.

The rail is discharged through the front of the unloading wagon car in a manner such that this wagon car, upon coming to a stop, pushes the new rail before it.

These devices present the following disadvantages:

-   -   the clamping hook requires manipulation by the relevant         personnel,     -   the railway wagon car comprises only one single unloading device         for unloading of rails per rail line, at the front of the wagon         car, in a manner such that the removal of the rail by making use         of the said hook must be done in several steps;     -   the drive tracked belt, which is located under the rail, moves         the rail away from the deck of the railway wagon car such that         the rail is discharged from a height that is significantly         higher than that of the deck of the railway wagon car; this         increases the height of the drop of the rail and the latter         therefore has an unsupported portion, lying between the         unloading device at the front of the railway wagon car and the         first sleeper on which it rests, which is longer than if it         would have dropped from the railway wagon car from the height of         the wagon deck;     -   the pulleys (or the second tracked belt), which rest on the head         of the rail, carry the risk of damaging the running surface;         however there exist special requirements in this field in the         construction of High Speed Rail (HSR) lines.

The invention proposes to resolve these problems. To this end, it proposes a railway wagon car for the laying of continuous lengths of rails on a railway platform, the said railway wagon car having a rear end hitched to a rail transport wagon car and a front end, characterised in that it may further comprise the following:

-   at the rear end thereof, at least one means for longitudinal removal     of a rail from a stored stock of rail arranged on the said rail     transport wagon car, -   at least one first means for driving the rail such as to move the     said rail to the front of the said railway wagon car, the said first     drive means grabs up the said rail between two motor driven crawler     track systems, each comprising a tracked belt sent around between     two wheels, the said crawler track systems being provided so as to     take a relative position in which the said tracked belts face each     other and the axles of the said wheels are vertical.

Such a railway wagon car is part of a railway track construction train that lays rails in a single continuous process, having a plurality of railway wagon cars, comprising therein wagon cars for transporting long rails, and one or more locomotives. The railway platform is the top surface of an embankment built in accordance with highly exacting standards in order to receive one or more railway tracks.

The railway wagon car according to the invention is designed for the unloading and the laying of long rails, whether directly on the platform, or on the sleepers previously laid out on this platform. It is located at the front of the train for laying new tracks; behind it are hitched the long rails transport wagon cars.

It is characterised by the presence of two means:

-   -   one means that makes it possible to remove the rails one by one         from the stock of rails that are found at least in part on the         transport wagon car which is hitched thereto, and to bring close         the front end of a rail of a first drive means, in a manner so         as to cause the rail to engage with this first drive means,     -   a first drive means at the rear of the railway wagon car, in         order for exerting a tractive force on the rail, making it slide         towards the front of the wagon with a view to the laying thereof         on the platform.

Advantageously, the railway wagon car may also comprise at its front end, at least one second drive means for driving the rail in order to push the said rail out of the said railway wagon car and towards the front thereof, the said second drive means grabs up the said rail between two motor driven crawler track systems, each comprising a tracked belt sent around between two wheels, the said crawler track systems being designed such as to take a relative position in which the said tracked belts are made to face each other and the axles of the said wheels are vertical.

This railway wagon car is characterised in particular by its means for driving the long rails, each of which comprises at least two crawler track systems, each having one tracked belt going around in a continuous closed loop between two wheels, for example two gear wheels or pinions, comprising one drive gear wheel, or one drive gear wheel and one pulley. The at least one first drive means, at the rear of the railway wagon car, takes up the rail after its removal from the transport wagon car and moves it forward towards the front of the railway wagon car, the at least one second drive means, at the front of the railway wagon car, discharges the rail on to the platform by “pushing” it to the front of the railway wagon car.

In operation, whether it is the first or the second drive means, the tracked belts of a crawler track system are made to face each other and the said wheels are with vertical axles, such that the crawler track systems are located on both sides of the rail and do not occupy any space below the rail. The rail is grabbed up from both sides laterally and not by the top and the bottom, the rolling surface of the rail thus is not subjected in this driving operation, to any force that is likely to damage it. Furthermore, this lateral arrangement of crawler track systems makes it possible to move around the rails, from the rear to the front of the railway wagon car, at almost the height of the deck of the railway wagon car.

Preferably, the railway wagon car comprises two first drive means at the rear and two second drive means at the front, in a manner such as to lay both the lines of rails of the same track simultaneously.

Advantageously, the said first and second drive means may comprise the means for moving away and bringing close the said crawler track systems in relation to each other, the said means being adapted in order that the two crawler track systems are supported on the said rail by gripping its web when they have moved close to each other, in a manner such as to be able to drive the said rail by friction.

The two tracked belts of a crawler track system are mounted on a support structure having actuating means in a manner such that they are able to move away from and come close to each other in order to grip the web of a rail when they have moved close together. When they grip the web of a rail, they are able to drive this rail by friction. When they have moved away from each other, the rail is freed.

This movement of drawing away from and coming close to each other is for example a movement of horizontal translation or rotation about a horizontal longitudinal axis.

Advantageously, the first and second drive means may comprise the motorisation means provided for driving each tracked belt in a coordinated manner with speed and in the direction of rotation with the one which is facing it.

The motorisation of the two crawler track systems of a same drive means, for example, by hydraulic motor, is coordinated in a manner such that the two tracked belts advance in the same direction and at the same speed when they grip a rail.

Advantageously, each tracked belt may comprise a plurality of elements connected in an articulated manner to each other, aligned along the direction of unloading, and equipped with feet on their outer surface, the said feet being shaped in order to fit the shape of the web of the said rail and comprising a material having a high coefficient of adhesion to the steel, preferably greater than 0.6.

The tracked belts are constituted of elements connected in an articulated manner to each other and comprise of feet on their outer surface. These feet are designed for gripping the web of the rail, they are thus shaped to fit into the form of the web of the rail.

The rail feet are comprised of a material with high adhesion to steel so as to be able to exert a high tractive force on the rail without slipping when the crawler track systems grip the rail, typically more than 30 000 Dekanewton (daN). A coefficient of adhesion to steel greater than 0.6, preferably between 0.6 and 0.8 will be sought.

Advantageously, the at least one means of longitudinal removal may comprise of a rail pinch bar mounted at the end of a first telescopic arm or articulated arm.

The advantage is that this rail pinch bar can be remotely controlled. In this manner potentially dangerous human intervention may be avoided. It must exert a sufficient grip force on the long rail in order to enable the removal thereof from the rail transport wagon car.

The first telescopic arm or articulated arm makes it possible to exert on the rail a tractive force that is sufficient to cause it to slide on the storage racks and bring its front end close to the first drive means, then to cause the engaging of this rail on the first drive means.

Advantageously, each first drive means is secured under the fixed part of a respective first telescopic arm, in a manner such that the rail pinch bar directly presents the rail to the inlet of the first drive means.

Advantageously, the first telescopic arm can be mounted on a positioning means that enables the adjusting of the transverse position and/or the vertical position of the said first telescopic arm.

The rails stocked on the transport wagon are not all aligned along the rail running edge of the future railway track, they are distributed over the entire width of the transport wagon car and are distributed by height. It is therefore necessary, when a new rail is to be extracted from the storage racks, to position the rail pinch bar that is found at the end of a telescopic arm, above the end of this rail irrespective of its position in the racks. For this purpose the telescopic arm is mounted in a structure fixed to the rear of the railway wagon car and having the means for positioning transversely and along the vertical projection of the arm, cylinders for example. The slider of the telescopic arm also provides a means for longitudinal positioning. Once the rail pinch bar has gripped the rail, the latter may be eased by raising the telescopic arm in a manner so as to reduce friction of the rail on the racks.

Advantageously, the railway wagon car may in addition also comprise, between the said first drive means and the said second drive means, the guiding means for guiding the rail in a transverse position and in a vertical position relative to the said wagon car.

For the same reasons explained here above (different positions of the rail on the rail storage wagon car), the rail which is being discharged is not present on the railway wagon car exactly along the rail running edge of the future railway track. It is therefore necessary to place this rail along this rail running edge. To this end, the railway wagon car comprises, downstream from the first drive means, the means for guiding the rail in a transverse position and in a vertical position.

These guiding means may advantageously comprise of the following:

-   at least one roller with a horizontal axis transverse to the railway     wagon car and the means for controlling its heightwise position, -   and/or at least one roller with vertical axis and the means for     controlling the transverse and/or longitudinal position thereof     relative to the railway wagon car.

Advantageously, the railway wagon car may also comprise, between the guiding means and the second drive means, the alignment means for aligning the rail along the rail running edge.

The guiding means mentioned here above provide the ability to straighten the rail but are not sufficient for placing the rail exactly along the rail running edge. The alignment means provide the ability to align the rail on the rail running edge and to prevent the second drive means from being subjected to vertical axis torsional forces.

Advantageously, each second rail drive means may be mounted at the end of a second longitudinal telescopic arm or an articulated arm, in a manner such as to move the said second drive means away from the front of the railway wagon car.

The rail not being raised up to be above the floor of the railway wagon car, it is necessary to move it away from the front of the railway wagon car and in particular from the buffer stops when it is unloaded on to the platform. To this end, the second rail driving means are each arranged at the end of the slider of a respective second telescopic arm.

Advantageously, each second telescopic arm may be fastened to the railway wagon car by fastening means that enable the adjusting of the transverse position of the said second telescopic arm.

Based on the construction sites, the rails are not always laid in the same positional location relative to the axis of the track. For example, the rails may be laid on the sleepersin their permanent or temporary positional locations, or even on the platform adjacent to the sleepers. Consequently it is therefore advantageous to be able to adjust the transverse position in which the rails are laid on the platform. This adjustment is normally carried out once and for all for a given site, as a consequence it is thus not necessarily motorised, it may be carried out simply by bolting.

Advantageously, each second rail drive means may be mounted to be articulated on the said telescopic arm along a horizontal axis transverse to the railway wagon car.

The rail is unloaded on to the platform by being made to tilt in an incline which may go up to several degrees. To support this inclination, the second drive means are mounted so as to be articulated at the end of the respective telescopic arm, about a pivot of horizontal axis that is transverse to the railway wagon car.

Advantageously, the railway wagon car may also comprise at its front end the means for laying the end of the said rail on to the platform.

When the rear end of the rail being unloaded reaches the second drive means, it is necessary to provide for a means for controlling the descent of this end on to the platform. This means may advantageously comprise of a cable or a chain having a rail pinch bar at a first end, a return pulley for running the said cable or the said chain with transverse axis located at the free end of each second telescopic arm and an actuator such as a cylinder or a winch connected to the second end of the said cable or the said chain.

Advantageously, the railway wagon car may comprise a system for controlling the first and second drive means, provided for ensuring that at any moment in time, only one of the said drive means is activated.

The railway wagon car according to the invention comprises for each line of rail a first rail drive means at the rear and a second rail drive means at the front. Each of these drive means has the ability to tow a rail. In order to avoid the risk of desynchronisation of the means of driving and therefore of sliding of the rail between the tracked belts, and risk of deterioration of the rail feet, the railway wagon car is equipped with a control means for controlling these drive means which serves to ensure that at any moment in time, only one of these means is active. For example, the user will be unable to engage one of the drive means prior to the other one being disengaged.

Advantageously, the railway wagon car may further comprise at the front a welding means for welding the rails and a means for handling the welding means provided for moving the said welding means between a rest position on the railway wagon car and a welding position on one of the rails of the track under construction.

The welding means may for example consist of an electric welding head; this welding head is manipulated by an articulated arm mounted on a sliding support in order to launch it over to the front of the railway wagon car. This articulated arm may in addition have at least two degrees of freedom with respect to its support, a horizontal axis of rotation for lowering and raising the welding head and a vertical axis of rotation in order to orient it towards the rail ends to be welded. Furthermore, the connection between the welding head and the articulated arm comprises a rotary joint so as to enable the aligning of the welding head and the placement thereof astride the rail ends to be welded.

The invention further relates to a method for laying rails using a rail pushing wagon car and a stock of rails arranged on a transport wagon car hitched to the rear of the said rail pushing wagon car, the said method comprising the steps consisting of:

-   gripping the web of a rail between two first motor driven crawler     track systems located at the rear of the said railway wagon car, the     tracked belts being driven around between two wheels with vertical     axles, -   longitudinally removing the said rail from the said stock of rails     by actuating the said first crawler track systems.

The method, in the first instance, consists of removing a rail from a stock of rails arranged on a rail transport wagon hitched to the rear of the railway wagon car with the help of two crawler track systems with vertical axis, that is to say, each one having at least one drive means such as a gear wheel with vertical axis. The crawler track systems grip the web of the rail and drive it by means of friction.

Once the rail has been extracted from its storage position, the method may comprise the steps consisting of:

-   gripping the web of a rail between two second motor driven crawler     track systems located at the front of the said railway wagon car,     the said tracked belts being driven around between two wheels with     vertical axles, -   unloading the said rail from the front of the railway wagon car by     actuating the said second crawler track systems.

According to the method, the grip of the first crawler track systems on the rail is released when the rail is towed by the second crawler track systems.

Various embodiments and variants shall be described hereinafter, by way of non-limiting examples, with reference being made to the attached drawings in which:

FIG. 1 shows a representative overview of a rail pushing wagon car in perspective,

FIGS. 2A and 2B represent partial views in perspective of the rear part of the rail pushing wagon car,

FIG. 3 represents a perspective view of a rail guiding device,

FIG. 4A and FIG. 4B represent views in perspective, respectively from above and below, a partial view of the front part of the rail pushing wagon car,

FIG. 4C represents a view in perspective of a front telescopic arm of the rail pushing wagon car,

FIGS. 5A and 5B represent two crawler track systems gripping a rail respectively in perspective and in vertical cross sectional views,

FIGS. 5C and 5D represent views in perspective respectively of a crawler track system with and without its cowling,

FIGS. 6A and 6B represent views in perspective of a front portion of the railway wagon car comprising an electric welding station, respectively in the retracted position and in the operational position.

FIG. 1 illustrates a rail pushing car (RPC) 100 in its entirety. This railway car has a rear portion 200, a central portion 300 and a front portion 400.

The RPC is constructed on a conventional flat wagon car base that comprises a chassis 40 defining a deck 50, a rear bogie 60 and a front bogey 70.

At the rear of this railway wagon car is hitched a rail transport wagon car not shown. This transport wagon car carries in part the long rails to be laid, stored on racks, positioned on their feet.

The central portion 300 comprises a conventional technical zone: generator, hydraulic unit, electrical cabinet, etc. such that the RPC is energy independent. It is covered so as to protect the personnel from the overhead catenary systems. The equipment in this technical zone are disposed axially in the railway wagon, in a manner so as to leave on both sides two longitudinal “corridors” for the passage of the two rails being laid.

The RPC comprises a rear control station 201 and a front control station 401 on either side of the central portion 300.

The rear portion 200 comprises two first telescopic arms or rear arms 202 a, 202 b, each comprising of a fixed part and a sliding part or the slider. These telescopic arms are integrally secured to a fixed structure 203 by means of a respective positioning mechanism for positioning these arms which will be described later. This fixed structure is composed of two flanges 204 a, 204 b that rise laterally on either side of the deck 50 of the railway wagon car and a substantially rectangular horizontal frame 205, below which are fixed the said mechanisms.

Under the fixed part of each of the telescopic arms are fixed two crawler track systems 220 a, 220 b (not visible), 202 c, 202 d (not visible). The crawler track systems which are facing each other are mounted so as to be pivotable about a longitudinal axis X-X′ located under the telescopic arm. When they are brought close by means of rotation around this axis X-X′, they grip the rail R1, R2 on both sides of the rail web.

These crawler track systems are described further here below in connection with the FIGS. 5A and 5B.

The front portion 400 comprises two second telescopic arms or front arms 402 a, 402 b, of which the fixed parts are integrally secured to a fixed structure consisting of the side drop panels of the wagon and cross beams 403 b, 403 c, the front arms 402 a, 402 b being fastened under the said beams. The crawler track systems 420 a to 420 d are fixed under the front arm.

In FIG. 1, the front and rear telescoping arms are retracted.

FIGS. 2A and 2B are partial views of the rear portion 200 of the RPC. It comprises a fixed frame 205 under which are fixed the horizontal and longitudinal telescopic arms 202 a, 202 b.

As illustrated in FIG. 2B, the positioning system for the telescopic arm 202 a comprises of a deformable parallelogram consisting of:

-   -   a horizontal cradle 204, secured under the fixed frame 205; this         cradle is connected to the said frame by means of a transverse         slide link, which provides the ability to move the telescopic         arm transversely relative to the railway wagon car,     -   a rear leg 205 and a front leg 206 each mounted to be pivotable,         at their upper end to the said cradle 204 and at their lower end         to the fixed part of the sliding arm 202 a, along the transverse         axis,     -   the fixed part of the sliding arm 202 a.

In order to obtain the deformation of this parallelogram, the positioning system further comprises of:

-   -   a non-deformable triangle T with vertices A, B and C, the         segment AC corresponding to the said front leg 206;         consequently, the triangle T thus is connected to the cradle 204         by a pivot C and to the sliding arm 202 a by a pivot A;     -   an actuator such as a cylinder 207, situated between the said         front and rear legs, mounted to be pivotable at its upper end to         the said cradle 204 and at its lower end to the vertex B of the         triangle.

The actuation of the cylinder 207 causes the triangle T to pivot about the pivot C which causes the deformation of the parallelogram, such that the sliding arm 202 a is able to move according to a swing like motion, that is to say, from front to back and rising up and descending all while remaining horizontal.

This positioning system makes it possible to provide individually to the rear telescopic arms different positions in the transverse, vertical and longitudinal direction.

They each have at the end of their sliding part, that is to say, oriented towards the transport wagon car, a rail pinch bar 210 a, 210 b, each provided for gripping a rail R1, R2 as shown in FIG. 2A. These rail pinch bars are preferably self-locking rail pinch bars.

On the one hand, the vertical and transverse positioning system of the arm, and on the other hand, the fact that they are telescopic, make it possible to position the rail pinch bars 210 a, 210 b above the front end of the stock of rails and to grab the whole rail from the stock, whatever be its position in the rail stock.

For the rail running edge corresponding to the rail R1, the removal of a rail from the stock comprises the following steps:

-   -   telescopic arm 202 a in high and retracted position,     -   rear crawler track systems 220 a, 220 b moved away from each         other,     -   opening of the rail pinch bar 210 a,     -   release of the telescopic arm 202 a and transverse positioning         above the rail R1 to be extracted,     -   lowering of the telescopic arm 202 a by deformation of the         parallelogram, far enough to position the rail pinch bar 210 a         so as to engage with the rail,     -   gripping of the rail R1 to be extracted by the rail pinch bar         210 a,     -   partial removal of the rail R1 by retracting the telescopic arm         202 a far enough to engage the end of the rail between the         tracked belts of the rear crawler track systems 220 a, 220 b,     -   clamping by the crawler track systems on both sides of the rail         web,     -   opening of the rail pinch bar,     -   actuation of the rear crawler track systems in order to remove         the rail from the rail stock and to move it forward to the front         of the railway wagon car.

All of these movements are controlled from the rear control station 201.

The intermediate guiding device 500 illustrated in FIG. 3 is located downstream from the telescopic arms 202 a, 202 b. It is necessary for straightening the rails in the process of being laid and for supporting them during their transit through the railway wagon car. Indeed, as has previously been seen above, most of the rails in the rail stock are not placed in alignment with the rail running edge and therefore it is necessary to guide them to the means of alignment on the rail running edge that is intended for them by playing on their flexibility. For this purpose, the guiding device comprises of:

-   -   two rollers with transverse horizontal axles 501 a, 501 b, the         vertical position of each roller being controlled by a         respective actuator 502 a, 502 b, these rollers being intended         to support the rail,     -   two rollers with vertical axles 503 a, 503 b, the transverse         position of each roller being controlled by a respective         actuator 504 a, 504 b.

In the illustrated embodiment, these rollers are not motorised.

FIGS. 4A and 4B are partial views of the front portion 400 of the railway wagon car and FIG. 4C is a view of a front telescopic arm. This front portion comprises two front telescopic arms 402 a, 402 b, whose fixed part is secured under the cross beams 403 b, 403 c. These telescopic arms 402 a, 402 b are secured to the said beams by means of gripping jaws 405 so as to allow the adjustment of their transverse position relative to the railway wagon car when necessary, for example by bolting. These front telescopic arms, when they are deployed, perform the function of moving the rails in the process of being laid away from the front of the railway wagon car and in particular from the buffer stoppers.

Two crawler track systems 420 a, 420 b, 420 c, 420 d, identical in principle to the rear crawler track systems 202 a to 202 d of the railway wagon car, are mounted at the front end of the sliding part of each telescopic arm and under this end. When these crawler track systems grip a rail by its web, they enable the pushing of the rails to the front of the railway wagon car in order to unload them on to the platform. They are described further below in connection with FIGS. 5A and 5B.

The crawler track systems are connected to the telescopic arms by way of booms mounted to be articulated about an axis Y-Y′ that is horizontal and transverse relative to the railway wagon car, in a manner so as to follow the curvature of the rail as it leaves the railway wagon car.

The end of the slides of each front telescopic arm 402 a, 402 b comprises a return pulley 406 a, 406 b intended for facilitating the laying of the rail end on the platform. In order to prevent the rail end from falling hard on the platform after having passed over the front crawler track systems, the operator has a rail pinch bar on the end of the rail when it is present, this rail pinch bar being connected to a cable or a chain that is run over the said return pulley 406 a, 406 b, the other end of the cable or chain being connected to an actuator such as a cylinder or a winch (not shown). Thanks to this device, the operator is able to control the descent of the rail end on to the platform.

Upstream of the front tracked belts 420 a to 420 d there are two pairs of alignment rollers 410 a, 410 b having a vertical axis, designed for running on both sides of the rail web. Each pair of rollers is mounted on a chassis 411 a, 411 b, itself mounted so as to slide along the length of a cross beam 412. Their transverse position is adjustable by the operator. Their function is to transversely align the rail on the telescopic arm. In the illustrated embodiment, these rollers are not motorised.

FIGS. 5A and 5B illustrate two crawler track systems 620 a, 620 b gripping a rail R1. The crawler track systems are composed of elements 622 connected to one another in an articulated manner, forming a closed chain, and having a foot on their external surface. These feet are designed to have a high coefficient of friction with steel, for example they are made out of rubber. The feet advantageously have a slightly convex shape in order to fit into the profile of the rail web and thus obtain the largest possible bearing surface.

The tracked belt is driven in motion by a drive gear wheel 630 or by any other means, itself driven by a hydraulic motor 621, 621 a, 621 b. In operation, that is to say, when the crawler track systems grip the web of a rail, the axles of the drive wheels of the crawler track systems are substantially vertical. FIG. 5B illustrates the clamping movement of the crawler track systems 620 a, 620 b about the axis X-X′ for gripping the rail R1.

FIGS. 5C and 5D illustrate an isolated crawler track system. The tracked belts move between two flanges, one top flange 625, 625 a, 625B, and one bottom flange 626, 626 a, 626 b. The top flange 625 comprises two yokes 627 a, 627 b for the fastening and the articulation of the crawler track system. Each yoke has a pivot point or articulation point 628 a, 628 b about a horizontal longitudinal axis X-X′ and a tow point 629 a, 629 b upon which can come to be fastened for example a cylinder (not shown). These cylinders control the angular position of the crawler track systems about the axis X-X′, and allow for pressing down on the web of the rail being pulled.

The tracked belt is a closed chain composed of elements 622 connected in an articulated manner to each other and driven by a gear wheel 630. Opposite this gear wheel, the chain is sent around on a pulley 631 mounted on a yoke 632, which ensures the tension of the chain.

FIGS. 6A and 6B illustrate an embodiment of the rail pushing wagon car having, at its front end, an electric welding station 710, associated with the handling means 700 thereof that makes it possible to raise the welding station and to position it astride the rail ends to be welded. The assembly is secured to the cross beams 403 a, 403 b, 403 c, themselves secured to the upper part of the side drop panels of the wagon.

The handling means 700 comprises of:

-   -   a carriage 703 capable of moving along the length of the         longitudinal rails 720 a, 720 b, so as to carry on beyond the         welding station 710 to the front of the railway wagon car,     -   a turret 701 mounted so as to rotate about a vertical axis Z-Z′         over the carriage 703, in a manner so as to position the welding         station 710 at the vertical of the rails to be welded, as shown         in FIG. 6B,     -   a dual handling arm 702 mounted so as to pivot about a         horizontal axis integrally secured to the turret 701; the         inclination of this arm is controlled by two cylinders 704 a,         704 b. The arm 702 consists of two parts which meet at an         attachment point 702 a at which the welding station 710 is         connected, such that when the welding station is in the rest         position on the turret 701, it is located between the two parts         of the arm, as shown in FIG. 6A.

The welding station 710 is connected to the attachment point 702 a by means of a rotary seal 715, in a manner so as to allow the operator to align the welding station on the rails to be welded.

Other embodiments apart from those described here above are covered by the invention:

-   -   the railway wagon car could comprise only one single drive means         per line of rail,     -   the crawler track systems could move in a horizontal plane and         grip the rail web by way of translation and not by rotation. 

1. A railway wagon car (100) for the laying of long rails on a railway platform, the said railway wagon car having a rear end (200) hitched to a rail transport wagon car and a front end (400), characterised in that it further comprises the following: at the rear end thereof (200), at least one means for longitudinal removal (202 a, 202 b, 210 a, 210 b) of a rail (R1, R2) from a stored stock of rail arranged on the said rail transport wagon car, at least one first means for driving the rail such as to move the said rail to the front of the said railway wagon car, the said first drive means grabs up the said rail between two motor driven crawler track systems (220 a, 220 c) each comprising a tracked belt sent around between two wheels, the said crawler track systems being provided so as to take a relative position in which the said tracked belts face each other and the axles of the said wheels are vertical.
 2. A railway wagon car for the laying of long rails according to claim 1, characterised in that it comprises at its front end (400), at least one second drive means for driving the rail in order to push the said rail out of the said railway wagon car and towards the front thereof, the said second drive means grabs up the said rail between two motor driven crawler track systems (420 a, 420 b, 420 c, 420 d) each comprising a tracked belt sent around between two wheels, the said crawler track systems being designed such as to take a relative position in which the said tracked belts are made to face each other and the axles of the said wheels are vertical.
 3. A railway wagon car for the laying of long rails according to claim 1, characterised in that said first and second drive means comprise the means for moving away and bringing close the said crawler track systems in relation to each other, the said means being adapted in order that the two crawler track systems are supported on the said rail by gripping its web when they have moved close to each other, in a manner such as to be able to drive the said rail by friction.
 4. A railway wagon car for the laying of long rails according to claim 1, characterised in that said first and second drive means comprise the motorisation means (621, 621 a, 621 b) provided for driving each tracked belt in a coordinated manner with speed and in the direction of rotation with the one which is facing it.
 5. A railway wagon car for the laying of long rails according to claim 1, characterised in that each track comprises a plurality of elements connected in an articulated manner (622) to each other, aligned along the direction of unloading, and equipped with feet on their outer surface, the said feet being shaped in order to fit the shape of the web of the said rail and comprising a material having a high coefficient of adhesion to the steel, preferably greater than 0.6.
 6. A railway wagon car for the laying of long rails according to claim 1, characterised in that said at least one means of longitudinal removal comprises of a rail pinch bar (210 a, 210 b) mounted at the end of a first telescopic arm (202 a, 202 b) or articulated arm.
 7. A railway wagon car for the laying of long rails according to claim 6, characterised in that said first telescopic arm is mounted on a positioning means (204, 205, 206, 207, T) that enables the adjusting of the transverse position and/or the vertical position of the said first telescopic arm (202 a, 202 b).
 8. A railway wagon car for the laying of long rails according to claim 2, characterised in that it further comprises, between the said first drive means and the said second drive means, the guiding means for guiding (500) the rail in a transverse position and in a vertical position relative to the said wagon car.
 9. A railway wagon car for the laying of long rails according to claim 8, characterised in that the said rail guiding means comprise of the following: at least one roller with a horizontal axis (510 a, 501 b) transverse to the railway wagon car and the means for controlling its heightwise position (502 a, 502 b), and/or at least one roller with vertical axis (503 a, 503 b) and the means for controlling the transverse and/or longitudinal position thereof (504 a, 504 b) relative to the railway wagon car.
 10. A railway wagon car for the laying of long rails according to claim 8, characterised in that it further comprises, between the said guiding means and the said second drive means, the alignment means (410 a, 410 b, 411 a, 411 b, 412) for aligning the rail along the rail running edge.
 11. A railway wagon car for the laying of long rails according to claim 2, characterised in that each second rail drive means is mounted at the end of a second longitudinal telescopic arm (402 a, 402 b) or an articulated arm, in a manner such as to move the said second drive means away from the front of the railway wagon car.
 12. A railway wagon car for the laying of long rails according to claim 11, characterised in that each second telescopic arm is fastened to the railway wagon car by fastening means (405) that enable the adjusting of the transverse position of the said second telescopic arm (402 a, 402 b).
 13. A railway wagon car for the laying of long rails according to claim 11, characterised in that each second rail drive means is mounted to be articulated on the said telescopic arm along a horizontal axis (Y-Y′) transverse to the railway wagon car.
 14. A railway wagon car for the laying of long rails according to claim 11, characterised in that it further comprises at its front end the means for laying the end of the said rail on to the platform.
 15. A railway wagon car for the laying of long rails according to claim 14, characterised in that said rail laying means comprises of a cable or a chain having a rail pinch bar at a first end, a return pulley (406 a, 406 b) for running the said cable or the said chain with transverse axis located at the free end of each second telescopic arm (420 a, 420 b) and an actuator such as a cylinder or a winch connected to the second end of the said cable or the said chain.
 16. A railway wagon car for the laying of long rails according to claim 2, characterised in that it comprises a system for controlling the first and second drive means, provided for ensuring that at any moment in time, only one of the said drive means is activated.
 17. A railway wagon car for the laying of long rails according to claim 1, characterised in that it further comprises at the front a welding means (710) for welding the rails and a means for handling (700) the said welding means provided for moving the said welding means between a rest position on the railway wagon car and a welding position on one of the rails of the track under construction.
 18. A method for laying rails using a rail pushing wagon car (100) and a stock of rails arranged on a transport wagon car hitched to the rear of the said rail pushing wagon car, the said method comprising the steps consisting of: gripping the web of a rail (R1, R2) between two first motor driven crawler track systems (220 a, 220 c) located at the rear of the said railway wagon car, the said tracked belts being driven around between two wheels with vertical axles, longitudinally removing the said rail from the said stock of rails by actuating the said first crawler track systems.
 19. A method for laying rails according to claim 18, characterised in that it further comprises the following steps: gripping the web of a rail between two second motor driven crawler track systems (420 a, 420 b, 420 c, 420 d) located at the front of the said railway wagon car, the said tracked belts being driven around between two wheels with vertical axles, unloading the said rail from the front of the railway wagon car by actuating the said second crawler track systems.
 20. A method for laying rails according to claim 19, characterised in that the grip of the first crawler track systems on the rail is released when the rail is towed by the second crawler track systems. 